JP2000261613A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent uneven image density without generating uneven light receiving amount due to flaws, even when light outputted from a light emitting element is almost a collimated light with respect to an image read optical axis in the case that the light emitting element with less generating heat and a high color temperature such as an LED is used for a light source. SOLUTION: In addition to a main light source 66 on an image reading optical axis, a secondary light source 82 with an optical axis tilted by a prescribed angle (30 degrees) with respect to the optical axis of the main light source 66 is provided at upper stream and a downstream of a photo film 22 receiving the light from the mainlight source 66 in its carrying direction. The light from the secondary light source 82 compensates for the scattering of the light of the main light source 66, resulting from the light nearly made collimated to supplement a deficient luminous quantity, so that the light of uniform luminous quantity can be emitted on a required area on the face of the photo film 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image reading apparatus which obtains image data by reading transmitted light or reflected light from a frame image while conveying a film on which a plurality of frame images are recorded.

[0002]

2. Description of the Related Art In recent years, a frame image recorded on a photographic film is photoelectrically read by a reading sensor such as a CCD, and image processing such as enlargement / reduction and various corrections is performed on digital image data obtained by the reading. In addition, a technique is known in which an image is formed on a recording material using a laser beam modulated based on digital image data that has been subjected to image processing.

As described above, in the technique of digitally reading a frame image using a reading sensor such as a CCD, the frame image is preliminarily read (so-called pre-scan) and the density of the frame image is read in order to realize accurate image reading. Reading conditions (for example, the amount of light applied to a frame image and CC
D, etc.), and the frame image is read again under the determined reading conditions (so-called fine scan).

In the above-described image reading system, a halogen lamp, which has been widely used for printing exposure and the like, is conventionally used as a light source. However, this halogen lamp generates a large amount of heat, and therefore, the luminous efficiency is low. Unfortunately, the increase in reading speed was limited.

That is, a halogen lamp is most suitable as a light source for directly printing on a photographic paper through a negative film as in the case of printing exposure. However, as described above, a CCD (usually for each of the three primary colors) is used. In a system that reads an image with a line CCD in which filters are attached so as to be sensitive to light, since the color temperature is low, the light amount of a short wavelength (B (blue) system in terms of color) is low, and the SN of the read image is low. Deteriorates (in terms of color, too much red). For these reasons, the halogen lamp has a problem in high-speed reading.

Further, a lamp having a high color temperature (for example, a xenon lamp, a metal halide lamp, etc.) has a problem that discharge noise occurs and reading cannot be performed with good image quality.

For this reason, it has been proposed to apply an LED as a light source. LEDs usually have a specific color (blue,
(Green, red), these are collectively arranged to form a white light source. LEDs generate less heat,
Since the color temperature is high, it is suitable as a light source for an image reading system.

On the other hand, the line CCD on the reading side is provided with a color filter for each line, and each line CCD detects the density (light amount) of each color.

[0009]

However, in the above-mentioned prior art configuration, the line CCD is efficiently used because the amount of light used is smaller than that of the halogen lamp.
Need to be supplied with light. For this reason, it is necessary to provide a configuration in which light from the LED is guided to the vicinity of the film surface by a fiber or the like, and all light is guided to a region near the film reading region.

When such light is used, most of the light becomes light perpendicular to the film surface (parallel light). If there is a scratch on the film surface, the light reflected on the scratch does not reach the line CCD, and the light is reflected at this portion. There is a problem that the amount of light is insufficient, resulting in an increase in image density. In the above-mentioned conventional halogen lamps and the like, a light diffusion plate is arranged before irradiating the film and light is sufficiently diffused, so that density unevenness to scratches does not occur.

In consideration of the above facts, the present invention considers the fact that when a light emitting element such as an LED, which generates a small amount of heat and has a high color temperature, is used as a light source, the light output from the light emitting element is substantially aligned with the image reading optical axis. It is an object of the present invention to provide an image reading apparatus that does not generate unevenness in the amount of received light due to scratches even with parallel light and can prevent unevenness in image density.

[0012]

According to a first aspect of the present invention, there is provided an image reading apparatus for reading an image by a predetermined color wavelength while transporting a film on which the image is recorded. A light emitting element that emits light in all of the color wavelengths is arranged in a line in the width direction of the film, a main light source that emits light with the film direction as an optical axis, and most of the light from the light source, Light guiding means for guiding in substantially the same direction as the optical axis, and a photoelectric conversion element that irradiates a film surface with the light guiding means and receives light transmitted or reflected on the film surface, and performs photoelectric conversion. A sub light source that is disposed around the optical axis of the main light source and outputs light at a predetermined angle with respect to the optical axis.

According to the first aspect of the present invention, the main light source guides the film surface substantially in the same direction as the optical axis to irradiate the film surface in order to effectively use a small amount of light.
On the other hand, when light is guided by the light guide means as described above, light is irradiated almost perpendicularly to the film surface, and if there is a flaw or the like on the film surface, it is assumed that the film surface has the same density. Assuming that the transmitted or reflected light is not uniform. Therefore, an appropriate image density cannot be obtained.

Therefore, a sub-light source for irradiating the film surface at a predetermined angle with respect to the optical axis is newly provided to compensate for a shortage of light amount due to a scratch. Since the auxiliary light source is disposed around the optical axis of the main light source, the amount of light received by the photoelectric conversion element should be stabilized (if the film surface has a uniform density, the amount of light received should be uniform). Can be.

According to a second aspect of the present invention, in the first aspect of the present invention, the predetermined angle of the auxiliary light source with respect to the optical axis of the main light source is 30 ° or more. .

According to the second aspect of the present invention, the angle (predetermined angle) of the sub light source with respect to the optical axis of the main light source is set to 30 ° or more. Thereby, instead of the light from the main light source that is scattered by the scratch, the light from the sub light source can be effectively used as the light received by the photoelectric conversion element.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the auxiliary light source has the same arrangement as the main light sources arranged in a row in the film width direction. The film is disposed upstream and downstream in the direction of transport of the film with respect to the position of the main light source.

According to the third aspect of the present invention, since both the main light source and the sub light source are arranged in a row along the width direction of the film, the light from the main light source and the sub light source is evenly distributed in the film width direction. Irradiation is possible, and it can sufficiently cope with scratches having various refraction angles.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the main light source and the sub light source are independent light sources. And

According to the fourth aspect of the invention, the main light source and the sub light source are independent light sources. Therefore, different LEDs having the necessary light amount for the main light source and the sub light source
LED that emits each color of RGB as main light source
LE with wide spectrum band (white light emission) for group and sub light source
The D group can be used, and the degree of freedom in design can be increased. In addition, by using an independent light source, for example, in the case of an old film, it is determined that there is much flaw, and the amount of the auxiliary light source is increased. Can also be reduced.

According to a fifth aspect of the present invention, in the first aspect,
The invention according to any one of claims 3 to 3, wherein the main light source and the sub light source are a common light source, and further include an optical path guiding means for irradiating the film surface with a predetermined optical axis in different optical paths. It is characterized by having.

According to the fifth aspect of the present invention, the main light source and the sub light source are used as a common light source, and a part of the light is irradiated substantially perpendicularly to the film surface as light used as the main light source. I do. In addition, another part of the light is emitted from the oblique direction (the predetermined angle) with respect to the film surface as a sub light source. To split the optical path from such a common light source, a light guide member such as a fiber is optimal, but the light may be split using an optical member such as a beam splitter. By using a common light source, the configuration of the device is simplified, and the light quantity control is also facilitated.

[0023]

1 and 2 show a schematic configuration of a digital lab system 10 according to the present embodiment.

As shown in FIG. 1, the digital lab system 10 includes a line CCD scanner 14, an image processing unit 16, a laser printer unit 18, and a processor unit 20. The processing unit 16 is integrated as the input unit 26 shown in FIG.
Are integrated as an output unit 28 shown in FIG.

The line CCD scanner 14 is for reading a frame image recorded on a photographic film such as a negative film or a reversal film.
5 size photographic film, 110 size photographic film, and photographic film with a transparent magnetic layer (24
0 size photographic film: so-called APS film), 12
Frame images of photographic film of size 0 and size 220 (Brownie size) can be read. The line CCD scanner 14 reads the above-mentioned frame image to be read by the line CCD 30, performs A / D conversion in the A / D converter 32, and outputs image data to the image processing unit 16.

In this embodiment, a digital lab system 10 in which a photographic film 22 of 135 size is applied will be described.

The image processing section 16 stores image data (scanned image data) output from the line CCD scanner 14.
Is input, and image data obtained by photographing with the digital camera 34 or the like, a document (for example, a reflection document, etc.)
Data obtained by reading the image data with a scanner 36 (flat bed type), image data generated by another computer and recorded in a floppy disk drive 38, MO drive or CD drive 40, and received via a modem 42 The communication image data and the like (hereinafter, these are collectively referred to as file image data) can be input from the outside.

The image processing section 16 stores the input image data in the image memory 44, and stores a color gradation processing section 46, a hypertone processing section 48, and a hyper sharpness processing section 50.
Image processing such as various corrections and the like, and outputs the image data to the laser printer unit 18 as recording image data. Further, the image processing unit 16 outputs the image data subjected to the image processing to an external device as an image file (for example, outputs the image data to a storage medium such as an FD, an MO, a CD, or to another information processing device via a communication line). Transmission, etc.).

The laser printer unit 18 includes R, G, and B laser light sources 52, and controls a laser driver 54 to record image data (temporarily stored in an image memory 56) input from the image processing unit 16. Is applied to the photographic printing paper, and scanning exposure (in the present embodiment, mainly the polygon mirror 58 and the fθ lens 60) is performed.
An image is recorded on the photographic paper 62 by an optical system using the same. Further, the processor unit 20 includes a laser printer unit 18.
The photographic paper 62 on which an image has been recorded by scanning exposure is subjected to color development, bleach-fixing, washing, and drying.
Thus, an image is formed on the printing paper.

(Configuration of Line CCD Scanner) Next, the configuration of the line CCD scanner 14 will be described. FIG. 3 shows a schematic configuration of an optical system of the line CCD scanner 14.

This optical system includes red (R), green (G),
Plural LED chips 6 that emit light in each of blue (B)
And a main light source 6 for irradiating the photographic film 22 with light.
6 is provided. The LED chips 64 are arranged in rows in the width direction of the photographic film 22 so as to be uniform for each color. Therefore, the light emitted from the main light source 66 becomes a white light source as a whole.

As shown in FIG. 4, the main light source 66
The optical axis is perpendicular to the irradiation surface of the photographic film 22. A light guide member 80 is disposed between the main light source 66 and the photographic film 22. One end surface of the light guide path member 80 is close to the main light source 66, and is cut to have a cylindrical lens function (not shown). For this reason, the light entering the light guide path member 80 is substantially parallel to the optical axis, output from the other end face, and irradiates the photographic film 22 surface. Although the incident end surface of the light guide member 80 is cut like a cylindrical lens, a cylindrical lens may be separately provided between the main light source 66 and the light guide member 80.

The photographic film 2 in the main light source 66
An auxiliary light source 82 is disposed on the upstream and downstream sides of the second conveyance direction independently of the main light source 66. The auxiliary light source 82 is an LED chip having a wide spectrum band (hereinafter, referred to as an LED chip).
84) are arranged in a row in the width direction of the photographic film 22, and the optical axis thereof is directed to the intersection of the optical axis of the light source 66 and the surface of the photographic film 22. I have. In other words, the sub light source 82 constituted by the broadband LED chip 84 has a predetermined angle θ with respect to the optical axis of the main light source 66 (θ = 30 in the present embodiment).
(The angle may be 30 ° or more). Note that the sub light source 82 may be an aggregate of LED chips that emit RGB light without using the broadband LED chip 84.

A light guide member 86 is provided between the sub light source 82 and the photographic film 22. Light emitted from the sub light source 82 is incident on one end surface of the light guide member 86. The output is made from the other end face.
Thus, the light from the sub light source 82 can be effectively used.

Here, as shown in FIG.
(Parallel light) is incident perpendicularly to the surface of the photographic film 22, so that the transmitted light faithfully has a light amount corresponding to the image density. On the other hand, as shown in FIG.
If a scratch 88 is formed on the surface of the photographic film 22, the scratch 8
The light incident on 8 is transmitted at a small angle with respect to the optical axis due to refraction on the surface of the scratch 88.

As shown in FIG. 7, when the light from the sub light source 82 is irradiated, the light from the sub light source is normally set at an angle of 30 ° or more with respect to the optical axis of the main light source 66. The light is incident on the surface 22, and is output as it is (with a slight refraction). However, as shown in FIG. 8, if the photographic film 22 has a scratch 88, the light becomes substantially parallel to the optical axis of the main light source 66 due to the refraction by the scratch 88, contrary to the main light source 66. As a result, as shown in FIG. 9, by simultaneously irradiating the main light source 66 and the sub light source 82,
Regardless of the presence or absence of 8, all the light in the irradiation area of the photographic film 22 is output in the optical axis direction of the main light source 66.

The main light source 66 and the sub light source 8 sandwich the photographic film 22 positioned and transported by the negative carrier 74.
On the side opposite to the side where 2 is provided, a lens unit 76 for forming light transmitted through the frame image and a 3-line CCD 30 are sequentially arranged along the optical axis of the main light source 66.

The three-line CCD 30 has a plurality of pixels for detecting light arranged in the width direction of the photographic film 22.
This is provided in three lines in the film transport direction. 3
The line CCD 30 is provided with a filter for receiving light of different wavelengths (RGB) for each line.

The light transmitted through the photographic film 22 is transmitted through a lens unit 76 (for example, a SELFOC lens).
An image is formed on the pixels of the line CCD 30.

Here, a function of accumulating electric charges (one-dimensionally) according to the light received sequentially from the pixel on one end side to the pixel on the other end side of each line is provided, and the photographic film is conveyed. Together with this, the frame image (two-dimensional) can be electrically read.

Here, the light received by the three-line CCD 30 is reliably combined with the light from the main light source 66 and the sub light source 82 regardless of whether the photographic film 22 has a scratch 88 or not. Since the light is uniformly irradiated within the range, it is possible to faithfully receive the light amount according to the density of the image. In other words, a photographic film of a certain density is
When the reading is performed at D30, the light receiving amount becomes uniform over the entire reading width.

The operation of this embodiment will be described below.

An operator inserts the photographic film 22 into the film carrier 74 and operates the keyboard 1 of the image processing section 16.
When the start of frame image reading is instructed by 6K, the transport of the photographic film 22 is started in the film carrier 74.
By this transport, a pre-scan is performed. That is, while the photographic film 22 is transported at a relatively high speed, the line CCD scanner 14 reads not only image frames but also various data outside the image recording area of the photographic film 22. The scanned image is
It is displayed on the monitor 16M.

At this time, the size of the frame image is recognized, and, for example, in the case of a panorama size frame image, light-through portions unique to the panorama size image (both ends in the width direction of the photographic film) are shielded.

Next, the reading conditions at the time of fine scanning are set for each frame image based on the prescan result of each frame image, and the reading conditions at the time of fine scanning are set based on the prescan result. It is set every time.

When the setting of the reading conditions at the time of the fine scan for all the frame images is completed, the photographic film 22 is set.
Is conveyed in the direction opposite to the prescan, and a fine scan of each frame image is executed.

At this time, since the photographic film 22 is being conveyed in the direction opposite to that in the pre-scan, the fine scan is executed sequentially from the last frame to the first frame.
The transport speed of the fine scan is set lower than that of the pre-scan, and the reading resolution is accordingly increased. In addition, at the time of pre-scanning, the image state (for example, captured image aspect ratio, under, normal, over,
Since the shooting state such as super-over and the presence / absence of flash shooting are recognized, it is possible to read under appropriate reading conditions.

Here, the line CC in the present embodiment
The main light source section 66 applied to the D scanner 14 employs an LED chip 64 instead of a halogen lamp or a xenon lamp which has been widely applied in the past.

The LED chips 64 are arranged substantially linearly at high density along the width direction of the photographic film 22 for each color.

Here, the light emitted from the main light source 66 passes through the light guide path member 80 and irradiates the photographic film 22 surface almost vertically (see FIG. 5).
In the three-line CCD 30, the pixels of each line receive light. In the three-line CCD 30, a filter for separately receiving RGB light is attached to each line, and as a result, it is possible to obtain a light amount for each of three colors corresponding to an image for each line.

As described above, by applying the LED chip as the light source 66, the characteristics of the LED such as high color temperature and low light amount of short wavelength are sufficiently exhibited, the SN of the read image is good, and the speed is high. Reading becomes possible.
That is, it is more suitable as a light source for reading an image than another light source such as a halogen lamp.

However, the LED chip 64 is disadvantageous in that the amount of light is insufficient. Therefore, most of the light emitted from the LED chip 64 is guided to the photographic film 22 by using the light guide path member 80 as in the present embodiment. As a result, the light is nearly parallel light and is incident on the photographic film 22 almost perpendicularly.

At this time, as shown in FIG. 6, if there is a scratch 88 on the surface of the photographic film 22, the scratch 88 scatters the incident light and deviates from the incident end face of the lens unit 76.
In some cases, uneven density was generated.

Therefore, in the present embodiment, a sub light source 82 is provided in addition to the main light source 66, and the light from the sub light source 82 is
Incline to photographic film 22 surface (incline of 30 ° or more)
And incident (see FIGS. 7 and 8).

As a result, as shown in FIG. 9, instead of the light scattered by the scratches 88 from the main light source 66, the light from the sub-light source 82 obliquely incident is refracted by the scratches 88 into an area where the amount of light is insufficient. Thus, the photographic film 22 can be irradiated with a substantially uniform light amount.

As described above, in the present embodiment, in addition to the main light source 66 on the image reading optical axis, the optical axis of the main light source 66 is located upstream and downstream of the photographic film 22 in the transport direction of the photographic film 22. In contrast, since the auxiliary light source 82 having the optical axis inclined at a predetermined angle (30 °) is provided, the photographic film 22 caused by making the light of the main light source 66 almost parallel light in order to compensate for the insufficient light amount. Scattering by the scratches 88 of the
Thus, it is possible to irradiate a required area on the surface of the photographic film 22 with a uniform light amount by compensating for the light from the photographic film 22.

In this embodiment, the main light source 66 and the sub light source 82 are provided independently. However, as shown in FIG. 10, a single light source 90 is connected to a linear fiber 92 for main light source light. The light serving as the main light source and the light serving as the sub light source may be extracted using the arc-shaped fiber 94 for the sub light source light, and may be separately guided on the photographic film 22. In this case, the ratio of the light for the main light source to the light for the sub light source is
Preferably, it is 1: 1.

In this embodiment, the photographic film 2
Although the target is a transmission film as in the case of No. 2, the present invention can be applied to reading of a reflection original.

In this embodiment, the LED chips constituting the LED chip groups 64R, 64G, 64B have a general structure in which the light emitting chips are embedded in a rectangular resin block. A reflective LED chip may be used, which includes a reflector having a shape, and the chip is arranged at a condensing position on the parabolic surface. In this case, the light emitted from the chip is reflected by the reflection plate and output as substantially parallel light, which is suitable for a configuration in which an image is read with color separation.

Although a selfoc lens is used as the lens unit 76, a disk-shaped general convex lens or concave lens may be used. However, the diameter is preferably relatively large in consideration of chromatic aberration and the like.

Further, three lines CC as photoelectric conversion elements
Although D30 is used, another photoelectric conversion element such as a MOS may be applied.

[0062]

As described above, in the image reading apparatus according to the present invention, when a light emitting element such as an LED, which generates a small amount of heat and has a high color temperature, is used as a light source, light output from the light emitting element is used for image reading. Even if the light is substantially parallel to the optical axis, there is an excellent effect that unevenness in received light due to scratches does not occur and unevenness in image density can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a digital laboratory system according to an embodiment of the present invention.

FIG. 2 is an external view of a digital laboratory system.

FIG. 3 is a perspective view showing a schematic configuration of an optical system of the line CCD scanner.

FIG. 4 is a front view of an optical system of the line CCD scanner.

FIG. 5 is a front view of a case where a scratch-free photographic film is irradiated using only a main light source.

FIG. 6 is a front view of a case where a scratched photographic film is irradiated using only a main light source.

FIG. 7 is a front view of a case where a scratch-free photographic film is irradiated using only a sub light source.

FIG. 8 is a front view of a case where a scratched photographic film is irradiated using only a sub light source.

FIG. 9 is a front view of a case where a scratched photographic film is irradiated using a main light source and a sub light source.

FIG. 10 is a front view showing an optical system when a main light source and a sub light source are used as a common light source according to a modification of the light source.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Digital laboratory system 14 Line CCD scanner 22 Photo film 30 Line CCD (photoelectric conversion element) 64 LED chip (light emitting element) 66 Main light source 76 Lens unit 80 Light guide member 82 Secondary light source 84 Broadband LED 86 Light guide member 88 Scratches

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C072 AA01 AA03 BA19 CA02 CA05 CA06 CA07 DA02 DA21 EA05 HA02 HA12 NA01 VA03 XA10 5F041 DA14 DB07 EE25 FF13

Claims (5)

[Claims] 1. An image reading apparatus for reading an image while transporting a film on which the image is recorded, comprising a light emitting element arranged in a line in a width direction of the film, and A main light source that irradiates light substantially vertically, a photoelectric conversion element that receives light transmitted or reflected on the film surface, and performs photoelectric conversion, and is disposed around the main light source, and receives light from the main light source. An image reading device, comprising: a sub-light source that irradiates a film irradiation surface with light at a predetermined angle. 2. The image reading apparatus according to claim 1, wherein a predetermined angle of the sub light source with respect to an optical axis of the main light source is 30 ° or more. 3. The main light sources arranged in rows in the film width direction are arranged in the same arrangement as the main light sources, and the upstream and downstream sides of the main light source in the transport direction of the film are arranged relative to the main light sources. The image reading device according to claim 1, wherein the image reading device is disposed in the image reading device. 4. The image reading apparatus according to claim 1, wherein the main light source and the sub light source are independent light sources. 5. The light source according to claim 1, wherein the main light source and the sub light source are a common light source, and further include optical path guiding means for irradiating the film surface with a predetermined optical axis in different optical paths. The image reading device according to claim 1.